The present invention relates to corrective lenses for diving masks, especially to corrective lenses for diving masks stacked over and arranged at a surface on one side of a lens of a diving mask for improving underwater vision.
According to users' needs, the diving mask is bonded with a pair of corrective lenses used to treat myopia, hyperopia, presbyopia, etc. Thus users/divers can see clearly underwater. Diving mask manufacturers provides a mask faceplate and a plurality sets of corrective lenses for vision correction. Thus users can select and install lenses directly into the mask faceplate according to their needs. However, specific tools are required for installation or replacement of the corrective lenses. Moreover, the operation of the specific tools follows instructions of manufacturers for preventing the lenses or the frame from being damaged. Once the user doesn't have sufficient experience in using the specific tools, there is a risk to damage the diving mask (is easy to get damaged). Moreover, the water tightness between the frame and the lenses is weakened after being assembled or replacing lenses. There is a risk of water leakage.
Refer to U.S. Pat. No. 7,699,462, a scuba diving mask with corrective lenses is revealed. The shortcoming of the device is in that the lenses of a scuba diving mask are replaced by corrective lenses. The corrective lenses are mounted on a frame detachably. There is still loss of water tightness of the mask. In order to improve the water tightness, the cost is increased. Moreover, refer to a product “Magnifier lens Assay Fresnel lens with the frame of bio-metal mask” in a catalogue of a Japanese Co. Apollo. A corrective lens is pivotally connected to a top surface of a diving mask frame. The corrective lens on the front side of the frame can be rotated vertically in relative to the frame. When the corrective lens is rotated downward to be in front side of the frame, it is used for better vision. The disadvantage of the product is in that the arrangement way of the corrective lens increases water resistance. This result in rotation and displacement of the frame the user wears. Moreover, such design has been applied to sunglasses broadly. Thus its patentability is concerned.